Report on Hydrothermal Conversion of Carbon Dioxide (CO2) to Fuels

This report provides an overview of the hydrothermal conversion of carbon dioxide (CO2) into fuels and other value-added products. It explores the significance of CO2 conversion as a response to environmental and energy concerns, emphasizing its role in reducing greenhouse gas emissions and fossil fuel dependence. The report discusses the hydrothermal process, highlighting its advantages such as the use of water as a reaction medium and its simulation of natural processes. It delves into the conversion of CO2 to formic acid and methanol, detailing research design, methodologies, and key performance indicators (KPIs) used to evaluate the process. Furthermore, the report examines the market potential of products like methanol and the economic, technological, and environmental aspects of the process, providing a comprehensive analysis of CO2 conversion strategies. The report also addresses the challenges in hydrothermal CO2 conversion such as developing efficient catalysts, reaction systems, and corrosion-resistant reactors.

Hydrothermal conversion of carbon dioxide (CO2) to fuels and other value added products 1
HYDROTHERMAL CONVERSION OF CARBON DIOXIDE (CO2) TO FUELS AND
OTHER VALUE ADDED PRODUCTS
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Hydrothermal conversion of carbon dioxide (CO2) to fuels and other value added products 2
Overview of research
The impact of fuel from the fossil to the energy portion in the globe will endure to be
greater than nuclear and renewable in medium and short tenure. Similarly, the course of
industries likes aluminium, iron, cement, paper and pulp, and processing plant, has intrinsic CO2
releases due to raw material conversion. Carbon capture and utilisation (CCU) denotes the
detention of anthropogenic CO2 and its successive application in a production route that uses
CO2 as fragment of carobn transporter (Aresta, Dibenedetto and Angelini 2013, pp. 66). Carbon
dioxide utilisations illustrate to the CO2 change procedure into a different product with profitable
value. The production of chemical and fuels from CO2 is mostly in the improvement phase
(Styring, Quadrelli and Armstrong 2014, pp. 35). Reliant on skills utlised to produce the ending
yield from CO2, the course is more or less profound to the contaminations in the stream of CO2,
for example, range from formic acid production to mineralisation. A high pure CO2 stream is
usually required by conversion procedure with the sensitive catalyst (Aresta, Dibenedetto and
Angelini 2013, pp. 1710). Currently, the quality of the stream of captured CO2 is determined by
the storage, transport and environmental needs and cost (Bruhn, Naims and Olfe-Kräutlein 2016,
pp.38). However, the quality remains uncertain in spite of the present experiences. Thus, carbon
dioxide utilisation is attracting the focus of policymakers as an alternative to the motive local
economies with suitable to install environmentally and economically feasible CDU plants.
Secondly to control the anthropogenic CO2 emissions and finally the potential lessening of CO2
emissions and fossil fuel dependence (Faberi, Paolucci, Ricci and Jiménez 2014).
Fuel synthesis from CO2 usually needs H2 as raw material. Hydrogen marketplace is
rising due to regulation in carriage fuel desulphurisation. It is projected that its international
request will escalate in the subsequent years. H2 is generated in huge amounts, both as by-

Hydrothermal conversion of carbon dioxide (CO2) to fuels and other value added products 3
product and main produce. About 96% of entirely H2 is derivative from fossil gases. Hydrogen
has the prospective to attain close zero CO2 performance when utilised. Therefore, its generation
has to be carbon-free sources to minimise the lifespan cycle CO2 emission.
The positioning of the research
The greenhouse effect is regarded as globe concerns that can cause a sequence of
disastrous occasions. To avert the problem, CO2 emission ought to be minimised as soon as
possible. For that reason, investigation dealing with CO2 fixation has fascinated much
consideration (Dominguez-Ramos, Singh, Zhang, Hertwich and Irabien 2015, pp. 148). One of
that is CO2 removal in the deep ocean site which can also be labeled as physical fixation. But,
such a task appears hard to carry out practically due to an absence of financial surety, even with
its technical lenience. Besides, the CO2 chemical reduction is considered as one of the most
projected answers to menace. Up to date, the hydrothermal drop of CO2 has been examined from
the ecological perspectives and was deliberated with the abiogenic creation of fossils gases.
The earth's surrounding is endangered by an upsurge in greenhouse gas CO2 in the
atmosphere that can be attributed to the rapid fossil fuels consumption. The change of the
greenhouse gas CO2 into high value-added chemicals and fuels is a feasible method to solve both
on the environmental and energy concerns. Many tactics for CO2 conversion have been
examined, for instance, CO2 catalytic hydrogenation, CO2 photocatalytic and electrochemical
conversion (Heyne and Harvey 2014, pp. 300). But, the above approaches have disadvantages
such as slow conversion rate, expensive metal catalyst and low efficiency. Thus, developing a
novel method for highly efficient and rapid CO2conversion is urgently required. Hydrothermal
reactions can be projected to have a highly effective, simple fast and environmental CO2

Hydrothermal conversion of carbon dioxide (CO2) to fuels and other value added products 4
transformation. This is because water is an environmentally friendly and hydrogen derived from
water can be directly used, and it entails a recyclable reaction medium. Secondly, hydrothermal
CO2 reduction simulates the natural occurrences of abiotic production of organics from CO2.
Finally, no high purity of CO2 is required. But, CO2 hydrothermal conversion still faces some
challenges such as developing of highly efficient and stable catalyst, development of a mild
reaction system and development of the reactor with the resisted corrosion characteristics. Thus,
the above challenges should be taken into consideration to accomplish the practical application
of CO2 hydrothermal reduction (Hu, Guild and Suib 2013, pp.19).
To minimise the volume of CO2 being produced, courses for recirculating carbon are
required, particularly those that do not necessitate too much energy and have high efficacies. The
hydrothermal reaction takes a crucial role in the fossil fuel formation. For instance, the change of
liquefied CO2 into hydrocarbon abiotically in the earth's layer and have revealed outstanding
potential for the quick transformation of a massive change of biomass into value-added yields.
Thus, if the geologic fossil fuels creation in nature could be joined with the hydrothermal
approaches being considered from material translations, a proficient system could be attained to
reprocess carbon and create chemicals.
Decarbonization knowledge requires scientific developments to get CO2 and change it to
other compounds and fuels. It will result in extensive utilisation of fossils fuels deposits with
carbon drawbacks and renewable resources. The hydrothermal process can assist improve the
remodeling and the gasification of numerous fuels with the skill to capture and changing CO2 to
valued chemicals and fuels (Bruhn, Naims and Olfe-Kräutlein 2016, pp.39). Using the apparatus
under hydrothermal conditions, CO2 can be transformed into formic acid or straight to methanol
using the many metals. For instance, in the two-stage hydrothermal course, it is probable to

Hydrothermal conversion of carbon dioxide (CO2) to fuels and other value added products 5
change CO2 to formic acid by utilising zero-valent metals in the intial process, while the
methanol is synthesised from formic acid in the subsequent phase using numerous minerals.
Fuel in the existence of gasifying elements, such as air or steam, under high temperature,
experiences chemical decay to yield a gas having, methane H2, CO2 and other chemicals in a
small amount. Hydrothermal reactions can be denoted as an aqueous chemical reaction under
high temperature from 200-3500C and high pressure of around 15 to 20MPa. These hydrothermal
reactions create bio-crude comprising organic acids, phenols and ketones. The first reaction in
hydrothermal situations is the hydrolysis of cellulose to glucose, which is the chief variance to
dry thermochemical transformation. Advance dehydration of the glucose hydrothermal reaction
in the presence of alkali can be used to change many biomasses into formic, acetic and lactic
acid. Lactic acid is used to create biodegradable lactic-acid centered polymers. Glucose from any
basis can be transformed into formic acid with a produce of 75% at a mild temperature of 2500c
in the existence of alkali as essential yield in the hydrothermal oxidation of carbohydrates.
Conversion of CO2 to formic acid
Hydrothermal change of biomass into compounds is an effective tactic as the high-
temperature elements of water is dissimilar from the water at ambient states. With the catalyst of
Cu and Ni, and also a small quantity of NaHCO3, the formic acid yield is approximately 48%.
Methanol is used widely as valued feedstock and fuel. It is easily divided from water matched
with formic acid. Using high temperature as the basis of Hydrogen, which can be produced using
inexpensive metals such as reductants, formic acids can be changed to methanol. Many metals
such as Cu and CU+ can react with water to create Hydrogen effectively under hydrothermal

Hydrothermal conversion of carbon dioxide (CO2) to fuels and other value added products 6
circumstances. The H2 is generated by the oxidation if metals could be dynamic to lessen the
formic acid into methanol.
Research design & methodology
Formic and methanol synthesis from CO2 are new industrial processes that are at different
phases of technology readiness (Li, Duan, Luebke and Morreale 2013, pp. 1440). Process
simulation models are constructed to evaluate their environmental, technological and economic
key performance indicators (Kothari, Buddhi and Sawhney 2008, pp. 553). The low TRL levels
denote that less data is accessible for model calibration and validation (input and output,
thermodynamics data) and also there is a high amount of uncertainty linked to the outcomes.
Data can be from laboratory experiments installation, commercial and pilot plants. These data
can become publically available through the patents, encyclopedias, scientific papers, and
companies web pages. For formic acid CDU, the information mainly comes from scientific
journals and primarily from the license; the only source found in the public domain depicting a
complete synthesis process for the chosen process in this study. For the methanol, the process
data primarily comes from scientific papers.
The aim of this work is to assess the reduction of CO2 over the manufacture of methanol
and formic acid by the CDU synthesis routes which are nearer to commercialisation. The study
estimates the potential to reduce CO2 emission from the plant point of view when compared to
the conventional synthesis process to generate methanol's and formic from the market
perspectives. Therefore, to address the above aspect, the study has defined a set of economic,
technological and environmental indicator that is quantified following a specific methodology.

Hydrothermal conversion of carbon dioxide (CO2) to fuels and other value added products 7
The part summarises the systematic methods used to assess the potential impact of the
CDU options addressed in the study. This work uses process flow modelling to get the energy
and mass equilibriums, the total acquisition price of the equipment and all the derived parameters
for the environmental, technological and economic evaluation of each plant. From the modelling
task, the net present value and tonnes of CO2 used per ton of product are the primary input to the
market and financial analyses. Overall, the report joins modelling; economic, technological and
environmental metrics evaluation; estimation of the market prospects; study of the profitability
through sensitive interpretations of the most crucial variables; comparison with the similar
conventional process to make each fuel (Kothari, Buddhi and Sawhney 2008, pp. 554).
The material and energy balance from the classical is an initial step to compute the
following chosen KPI. These signify various features of the procedure which are significant to
the entire CO2 emission. Technological parameters evaluate the CO2 and H2 that are changed in
the cauldron in the production route, and H2 and CO2 that are modified into the produce through
the complete course (Peters et al. 2011, pp. 1217). These are stated as a percentage of the overall
quantity of H2 or CO2 that go in the procedure as raw material. Economic metrics are costs
calculated in bottom-up tactics with the input info from the process framework. The
environmental parameters compare the CO2 balance, direct and indirect CO2 emission,
articulated in tonnes per ton of produce without taking into consideration the inlet quantity of
CO2. The market perspective aims at evaluating the future ultimatum of the product produced by
CO2, in view of present and probable novel utilisation (Markewitz et al. 2012, pp.7281).
Methanol is utilised for the manufacture of numerous industrial compounds. The primary
chemical derivative produced is dimethyl ether (DME), formaldehyde, methyl tertiary-butyl
ether and acetic acid. Methanol change into olefins, which can be used to make hydrocarbon is a

Hydrothermal conversion of carbon dioxide (CO2) to fuels and other value added products 8
developing sector. Methanol can be used in direct gasoline blending. Thus, the report refers to
the potential of MeOH as fuel. It can be utilised as hydrogen carrier or fuel, changed into its
derivatives or used as feedstock in the synthesis of olefins. Its manufacture and use, as a liquid
gas to substitute orthodox cradles of energy, make it attractive mostly for emerging economies
such as China (Markewitz et al. 2012, pp.7281).
The experiment will have micro-autoclave with a high-pressure regulator, reaction
chamber, cone packing sample and well of a thermocouple. The study will experiment the
produce of carbon-based composites and H2 at the various quantity of Ni. Fe: 100mmol, water:
33.6cm3 with filing rate of 70%, temperature of 300c at an experimental duration of 6 hours
(Quadrelli, Centi, Duplan and Perathoner 2011, pp. 1195)
The experiments will be piloted using a batch style micro autoclave scheme, lined with
Hastelloy-C, and quipped by a high-pressure regulator. A classic tentative process will be as
follows. Fe-powder, pure water and Ni powder will be injected to the reaction compartment, and
the reactor closed. Once air is replaced, CO2 gas will inject into the autoclave over the high-
pressure vent at the room temperature. Subsequently, the autoclave will be established in the
induction furnace (Porter, Fairweather, Pourkashanian and Woolley 2015, pp. 162). “The initially
substances will be treated hydrothermally by heating the autoclave to the experimental
temperature of 3000C at a heating phase of 30c/min while continually quaking” (Von der Assen,
Voll, Peters and Bardow 2014, pp. 7984). The autoclave will be taken out of the furnace and air-
conditioned to the room temperature. The vapor will be composed over the saturated salt solvent
and analysed by the GC armed with flame ionisation detector (FID) and thermal conductivity
detector (TCD). The residual blend will be sieved, and then the precipitous dried out in an
isothermal kiln for 24hours in 1100c. The liquid will be analysed with the GC armed with total

Hydrothermal conversion of carbon dioxide (CO2) to fuels and other value added products 9
organic carbon analyser, mass spectrometry detector and GC/FID, and x-ray diffractometer will
examine precipitous (Roddy 2012, pp. 460).
In a typical experiment, NI- powder, Fe-powder, CO2 and solvent is reacted in a batch-
sort of micro autoclave under hydrothermal settings for numerous hours (Rubin, Mantripragada,
Marks, Versteeg and Kitchin 2012, pp. 633). Formic acid, methane and H2 are made after water
treatment. With the increase of the Ni content, the methane output increase while formic and
hydrogen decreases. It is thought that Ni operates as catalyst in hydrogenation. In basic media,
CO2 converts to formic at 3000C intricate with methane traces, bearing in mind the decrease
features for the formic acid (Takeshita 2012, pp. 227).
A series of an experiment is conducted at 3000c for approximately 6 hours using Ni-
powder, Fe powder, water and CO2 gas (Aresta, Dibenedetto and Angelini 2013, pp. 1712). After
treatments, methane and hydrogen are chiefly produced, with a slight quantity of ethane and
formic acid. Precipitate examination reveals that Fe-powder is changed to Fe304 and FeCO3,
while Ni is displayed. Methane return increases with the increase of the Ni volume. Contrarily,
the H2 and formic acid yield decrease with the growing the Ni content (Faberi, Paolucci, Ricci
and Jiménez 2014).

Hydrothermal conversion of carbon dioxide (CO2) to fuels and other value added products 10
References
Aresta, M., Dibenedetto, A. and Angelini, A., 2013. Catalysis for the vaporization of exhaust
carbon: from CO2 to chemicals, materials, and fuels. Technological use of CO2. Chemical
reviews, 114(3), pp.1709-1742, ACS publications, [Online]. Available from:
https://pubs.acs.org/doi/abs/10.1021/cr4002758, [Accessed on 23 September 2018].
Aresta, M., Dibenedetto, A. and Angelini, A., 2013. The changing paradigm in CO2 utilization.
Journal of CO2 Utilization, 3, pp.65-73.elsevier, [Online]. Available from:
https://doi.org/10.1016/j.jcou.2013.08.001, [Accessed on 23 September 2018].
Bruhn, T., Naims, H. and Olfe-Kräutlein, B., 2016. Separating the debate on CO2 utilisation
from carbon capture and storage. Environmental Science & Policy, 60, pp.38-43, Elsevier,
[Online]. Available from: https://doi.org/10.1016/j.envsci.2016.03.001, [Accessed on 23
September 2018].
Dominguez-Ramos, A., Singh, B., Zhang, X., Hertwich, E.G. and Irabien, A., 2015. Global
warming footprint of the electrochemical reduction of carbon dioxide to formate. Journal of
Cleaner Production, 104, pp.148-155, Elsevier, [Online]. Available from:
https://doi.org/10.1016/j.jclepro.2013.11.046, [Accessed on 23 September 2018].
Faberi, S, Paolucci, L, Ricci,A, Velte, D. and I. Jiménez, 2014.“Methanol: a future transport fuel
based on hydrogen and carbon dioxide? Economic viability and policy options,”, [Online].
Available from: http://transport-research.info/sites/default/files/project/documents/
20150702_180206_47262_IPOLJOIN_ET2014527377_EN.pdf, [Accessed on 23 September
2018].
Heyne, S. and Harvey, S., 2014. Impact of choice of CO2 separation technology on thermo‐
economic performance of Bio‐SNG production processes. International Journal of Energy

Hydrothermal conversion of carbon dioxide (CO2) to fuels and other value added products 11
Research, 38(3), pp.299-318, wiley library, [Online]. Available from:
https://doi.org/10.1002/er.3038, [Accessed on 23 September 2018].
Hu, B., Guild, C. and Suib, S.L., 2013. Thermal, electrochemical, and photochemical conversion
of CO2 to fuels and value-added products. Journal of CO2 Utilization, 1, pp.18-27, Elsevier,
[Online]. Available from: https://doi.org/10.1016/j.jcou.2013.03.004, [Accessed on 23
September 2018].
Kothari, R., Buddhi, D. and Sawhney, R.L., 2008. Comparison of environmental and economic
aspects of various hydrogen production methods. Renewable and Sustainable Energy Reviews,
12(2), pp.553-563, Elsevier, [Online]. Available from: https://doi.org/10.1016/j.rser.2006.07.012,
[Accessed on 23 September 2018].
Li, B., Duan, Y., Luebke, D. and Morreale, B., 2013. Advances in CO2 capture technology: A
patent review. Applied Energy, 102, pp.1439-1447, Elsevier, [Online]. Available from:
https://doi.org/10.1016/j.apenergy.2012.09.009, [Accessed on 23 September 2018].
Markewitz, P., Kuckshinrichs, W., Leitner, W., Linssen, J., Zapp, P., Bongartz, R., Schreiber, A.
and Müller, T.E., 2012. Worldwide innovations in the development of carbon capture
technologies and the utilization of CO2. Energy & environmental science, 5(6), pp.7281-7305.
[Online]. Available from:
http://pubs.rsc.org/en/content/articlelanding/2012/ee/c2ee03403d/unauth#!divAbstract,
[Accessed on 23 September 2018].
Peters, M., Köhler, B., Kuckshinrichs, W., Leitner, W., Markewitz, P. and Müller, T.E., 2011.
Chemical technologies for exploiting and recycling carbon dioxide into the value chain.
ChemSusChem, 4(9), pp.1216-1240, wiley library, [Online]. Available from:
https://doi.org/10.1002/cssc.201000447, [Accessed on 23 September 2018].

Hydrothermal conversion of carbon dioxide (CO2) to fuels and other value added products 12
Porter, R.T., Fairweather, M., Pourkashanian, M. and Woolley, R.M., 2015. The range and level
of impurities in CO2 streams from different carbon capture sources. International Journal of
Greenhouse Gas Control, 36, pp.161-174, Elsevier, [Online]. Available from:
https://doi.org/10.1016/j.ijggc.2015.02.016, [Accessed on 23 September 2018].
Quadrelli, E.A., Centi, G., Duplan, J.L. and Perathoner, S., 2011. Carbon dioxide recycling:
emerging large‐scale technologies with industrial potential. ChemSusChem, 4(9), wiley online
library, pp.1194-1215. [Online]. Available from: https://doi.org/10.1002/cssc.201100473,
[Accessed on 23 September 2018].
Roddy, D.J., 2012. Development of a CO2 network for industrial emissions. Applied energy,
91(1), pp.459-465, Elsevier, [Online]. Available from:
https://doi.org/10.1016/j.apenergy.2011.10.016, [Accessed on 23 September 2018].
Rubin, E.S., Mantripragada, H., Marks, A., Versteeg, P. and Kitchin, J., 2012. The outlook for
improved carbon capture technology. Progress in Energy and Combustion Science, 38(5),
pp.630-671, Elsevier, [Online]. Available from: https://doi.org/10.1016/j.pecs.2012.03.003,
[Accessed on 23 September 2018].
Styring, P., Quadrelli, E.A. and Armstrong, K. eds., 2014. Carbon dioxide utilisation: closing the
carbon cycle. 1st ed, Elsevier, pp. 33-49.
Takeshita, T., 2012. Assessing the co-benefits of CO2 mitigation on air pollutants emissions
from road vehicles. Applied Energy, 97, pp.225-237, Elsevier, [Online]. Available from:
https://doi.org/10.1016/j.apenergy.2011.12.029, [Accessed on 23 September 2018].
Von der Assen, N., Voll, P., Peters, M. and Bardow, A., 2014. Life cycle assessment of CO 2
capture and utilization: a tutorial review. Chemical Society Reviews, 43(23), pp.7982-7994.
[Online]. Available from:

Hydrothermal conversion of carbon dioxide (CO2) to fuels and other value added products 13
http://pubs.rsc.org/en/content/articlelanding/2014/cs/c3cs60373c/unauth#!divAbstract, [Accessed
on 23 September 2018].